Pitman.



H. EICHHORN. PITMAN.

APPLICATION FILED 0GT.`19, 1908.

Patented July 25, 1911 HERMANN EICHHORN, OF ELIZABETH, NEW JERSEY,ASSIGNR TO THE SINGER MANUFACTURING COMPANY, A CORPORATION F NEW'JERSEY. l

Piraten.

SpecificationV of Letters' Patent.

Patented; Jury 25, ieri.

Application led October 19,1968. Serial No. 458,360.

',and useful Improvements in Pitmen, ,of vwhich the following 1s aspecification, re;t-

' erence being had therein to the accompany ing drawlngs.

This invention has for its object to( provide an effective andinexpensive construe tion for machine elements ofthat class 1nn volviinga stern with an eye or yoke adaptedv to-enibrace and afford an operativeconnec# tion with another relatively ,movable element disposed crosswisethereof as, for instance, a crank-and-pitman connection.

In certain light-running machines constructed to operate atcomparatively high speeds, and containing pitmen connecting rapidlyreciprocating arts, it is of great importance that theY pitmen bevconstructed of extreme lightness consistent with the requisite strengthand stiilness for perform ing their functions', so as to vavoid poundingand consequent noisy action and lack of durability; and the presentinvention is designed to provide a pitman. with these' qualities at acost not materially exceeding that involved in production by casting andconsiderably less than by drop-forging. By the foregoing methods ofconstruction, lightness was sacrificed for 'reduction of cost in thecasting processes, while a considcrable increase of production wasinvolved in the drop-forging processes.

According to the present invention a. machine element of the characterdescribed is formed of a sheet metal blank comprising a stem and anintegral cross-member, the lattcl' being bent with its face incrosswi'se relation with that of the stem and again in substantially theplane of the stem into the desired form, as ancye for embracing arotating .crank-pin such as the connecting rod Z of the sewing machineloop-taker mechanism formingthe subject of the United States patent toP'. Diehl and A. Grieb, No. 663,696, oi December 11, 1900. In order toinsure that the connected end ot' the eye shall be flush with theopposite face ofr the stem from. which such member projects, it isdesirable to form the cross! member at opposite edges of the stem withnotches of a depth substantially that of the thickness of the sheetmetal7 in order that .the cross-member may be bent upon a line beyondtheedge where it would other.- wise }o1n the stem; and the cross-memberpreferably projects farther from one edge than the other of the stem inorder that when rolled into circular form with its yends turnedoutwaitdly to form spaced ears for a clamping and an 'adjusting screw,such ears will be disposed :laterally thereof rather than in alinementwith the stem. v

In the. accompanying drawings, Figure 1 1s a face View oil a sheet metalblank suitable for producing apitmpn with eyes at opposite ends toembrace cylindrical pins upon relatively movable parts of a train ofmechanism rwhich the pltman is designed to operatively connect. Fig. 2is a similar view of said blank with the cross-members at the ends ofthe' stem bent at right angles to the latter, and Fig. 3 is an edge viewof the blank in the same stage of its formation, with one end portion insection. Fig. 4 is a face view ol the blank with the cross--transversely of the face of the stem and provided with lateral ears forapplication of clamp-screws Fig. 5 is a-perspective View of the pitmanwith the clamp-screws applied to its eyes or sockets.

The blank is stamped from sheet metal, and is thereforeA of uniformthickness throughout, and is composed of a stem l and a cross-member ateach end comprising the longer arm 2 a-nd shorter arm 3, both having attheir outer ends aperturesll for the clamp-screw or bolt 'in the inishedarticle.y The cross-member is provided adjacent its junction with' thestem 1, and at opposite edges of the latter, with the cuts or notches 5of a depth-corresponding substantially with the thickness ot' the blank.

In producing the iinished machine element, each end is first benttransversely of the face'of the stem l upon a line joining the innerends of the notches 5, whereby the adjacent edge of such cross-member ispermitted to assume a -flushrelation withthe face of the stem oppositewhich the body of the cross-member is bent. The cross-member is then'rolled into cylindrical form in a plane parallel with that of the stemto form the eye 6, with the end portions of the parts 2 and 3 turnedoutwardly and spaced apart slightly to form the parallel ears 7 Whoseapertnres are brought into alinement to receivethe clamping screw orbolt. As represented. in Fig. 5, a clamp-screw 8 is inserted through oneof such apertures and tapped.

into the other to serve as the clamping and adjusting means for theeyeji.

It is evident that the comparative lengths of the parts 2 and 3 ofthecross-member may be Yariedto suit the posit-ion for which the eleinentis designed, as also the shape into which the cross-member is rolled orbent, which is determined in practice by the use for which the articleis designed. v

Having thus Yset forth the nature of thev invention, what l claim hereinis A machine element 'composed of a flat sheet metal blank andcomprising a flat stem with an integral cross-member extendinglaterallyfrom said stem in both directions and bent from one facethereof and at right' angles thereto and again at right angles to therst bent portion and eoncentrically with a transverse axis to formasplit eye and then outwardly to form parallel spaced ears7 oneextremity of said eye being flush with the face of the stem oppositethat from which it projects, and means for drawing said ears together.

In testimony whereof, I have signed my name to this specification, inthe presence et two subscribing witnesses.

rHERMANN EICHHORN.

,Witnesses 1 D. RBIRNIE, H. J. MILLER.

